著者

松尾 泰佑 富田 隆 工藤 賢三 佐塚 泰之

出版者

一般社団法人日本医療薬学会

雑誌

医療薬学 (ISSN:1346342X)

巻号頁・発行日

vol.45, no.1, pp.54-60, 2019-01-10 (Released:2020-01-10)

参考文献数

9

被引用文献数

1

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Magnesium oxide tablets are sometimes crushed prior to administration to patients having difficulties in swallowing tablets. However, the quality of magnesium oxide formulations may decrease when stored for a long time as a one-dose package, owing to the absorption of high amounts of moisture by magnesium oxide. Additionally, as magnesium oxide solution is alkaline, it can interact with other medicines, making it incompatible for one-dose packaging. There are three types of magnesium oxide powder formulations: crushed magnesium oxide tablets, magnesium oxide bulk powder, and magnesium oxide granules. However, the appropriate formulation of magnesium oxide for one-dose packages is unknown. The stability of powder formulations stored as one-dose packages at 75% RH for 3 months was evaluated by analyzing the change in weight change and dissolution. The dissolution of the three powder formulations did not change for 3 months. Although the weight had increased in all the formulations, the change in the weight of magnesium oxide granules was the lowest among the three formulations. Isoniazid and levodopa tablets have been reported to interact with magnesium oxide tablets. The incompatibility between the crushed powder of these medicines and magnesium oxide powder formulations was analyzed when stored as one-dose packages. Among the three formulations, incompatibility was the lowest for granule. In conclusion, preserving magnesium oxide and other formulations that causes incompatibility should basically be avoided. However, magnesium oxide granules can be used for storing with the other formulations that interact with magnesium oxide within a term to circumvent incompatibility.

著者

松尾 泰佑 富田 隆 工藤 賢三 佐塚 泰之

出版者

一般社団法人日本医療薬学会

雑誌

医療薬学 (ISSN:1346342X)

巻号頁・発行日

vol.44, no.9, pp.464-470, 2018-09-10 (Released:2019-09-10)

参考文献数

8

被引用文献数

6

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Tablet splitting, an important task of the pharmacist, is performed at hospitals and health insurance pharmacies. Although magnesium oxide tablets have no score line, the accuracy of their division is not assured. Furthermore, as magnesium oxide strongly absorbs moisture, the stability of half-tablets is unknown when stored in one-dose packages. The variation and loss when splitting magnesium oxide 500 mg tablets by using a tablet-divider were evaluated. The stabilities of split tablets after storage in one-dose packages at 75%RH were evaluated through the analysis of weight change, disintegration, and dissolution. The variation in half-tablets of magnesium oxide 500 mg tablets was 5.5 ± 4.4% and the loss of almost all tablets was below 1%. Although the weight of the half-tablets increased when preserved in one-dose packages, this was related to the quantity of magnesium oxide stored in one-dose packages and not on the splitting of tablets. The disintegration time of half-tablets was prolonged by increased moisture absorption, but the disintegration time of split tablets was shorter than that of whole tablets when the same quantity of moisture was absorbed. The dissolution rate was similar among split tablets and whole tablets. Magnesium oxide tablets can be administrated as a split tablet, but caution should be exercised regarding prolonged disintegration time. Pharmacists should be careful when using half-tablets in prescriptions.